Numerical study of geometrical frustration: From square to triangular lattices Original Research Article

In this work we study the effects of geometrical frustration in square lattice which can be measured by the diagonal hopping integral. In the framework of the Hubbard model, we use quantum Monte Carlo method to calculate spin susceptibility and focus on magnetic fluctuations in this system. We find that in two filling regions, the effects of geometrical frustration are quite different. As a measure of geometrical frustration between square and triangular lattices, the diagonal hopping suppresses the anti-ferromagnetic fluctuation at half filling and enhances ferromagnetic fluctuation at 1.5 filling.